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Re: Treatment Free: It's a path, not a solution

In German studies, drones traveled up to 5 km. A single Drone Concentration Area had 238 separate colonies represented (based on mark and recapture studies). In an Arizona study, a 2 x 5 km block had multiple flyways and congregation areas (26!) where flyways crossed.

The discussion in both studies have drones making optimization decisions -- they distribute over several areas and optimize for time spent aloft, and mating likelihood.

A recent German study shows strong bias by drones to the closer DCA versus distant. No description of the Queen preference.

A obligate out-crossing mating system with promiscuous queens is going to maintain enormous variability in the F2 generation (i.e. the daughter queen's workers).

Most of the discussion on this forum conflates bee genetics with dog breeding. It is very different imperative-- the whole evolutionary strategy of the bee is stable morphology-- it is all about forcing flowers (and parasites) to evolve to what the bee desires, not changing the bee to the flower.

There is fascinating microsatellite studies of Mediteranean bees. In Algeria, where thousands of Italian queens were imported during the colonial period, there are zero Italian genetics in the mitochodria DNA-- it is all the native "Moroccan" subtype. Mitochondria descends outside the nucleus recombination-- and indicates the wild type has completely suppressed the "improved" introduction at tje queen level. This can be interpreted both as a case study in "local" races and as a cautionary tale about improving genetics in bees through wild out-crossing.

Yes you can change the genetics of the honeybee, but to maintain lines with high entropy, you need isolation and saturation. Think offshore islands (per Baton Rouge trials), multi-hundred unit daughter colonies surrounded by sterile water or cornfields. Saturation and Isolation-- the keys to moving an outcrossing genotype -- unless you have that the "selection" is going to revert very quickly. Remember the future colony will express the F2 generation in its social survival-- double hybrid distance from the mother queen.

If you are in a suburban backyard with a woodlot of hollow trees and a yard of 15 to 20 hives-- your genotype is going to regress to the wild norm-- simple and cruel mathematics. (Many of the most vocal advocates of TF beekeeping are in this type of apiculture).

In order to resolve whether this type of yard has any contribution to make to changing genotype through non-treatment selection, an evaluation of the "survivor hive" concept needs to be made. Two possibilities pertain: wild hives reflect the agricultural predominance of the southern queen breeders, or wild hives represent a unique "survivor genotype" local to the area. I haven't seen real evidence to support the "survivor hive" theory, but the published record is riduculously spotty for the core question. Some of my reluctance to embrace the "survivor hive" postulate is due to the Africanized Hybrid that increasing dominates my region -- the genetic drift is moving to AHB, and not to some other equilibrium.

Re: Treatment Free: It's a path, not a solution

Originally Posted by julysun

Is there any information, studies if you will, on how far drones travel to breed? Treated drones, I am sure you are aware, could hamper your TF work.

Friedrich Ruttner (Breeding Techniques and Selection for Breeding of the Honeybee) at first seems to recommend 8km between mating stations and unwanted genetics, though he seems to moderate this to 4km a little further on.

He also recommends raising vast numbers of drones from selected queens. His method is to tie in bits of drone comb to make whole frames, have them laid up by the selected queen/s, and then raised and housed in nursery hives that become 'drone colonies'.

He also talks about a 'guard ring' of such hives around the mating station, outlining the sorts of numbers required for mating a specific number of queens.

He speaks of the short lives of drones, and the need to co-ordinate drone-raising and mating requirements.

Re: Treatment Free: It's a path, not a solution

Of central interest to me is the idea that to get good breeding, we need to maintain drone yards, or drone colonies at least a mile from the apiary containing our mating nucs. Do we?

So quotes from the paper:

"Selected drone congregation areas were regularly observed for five years to verify that the dimensions of these congregation zones did not change greatly during this time (Ruttner and Ruttner 1968). When strange colonies were introduced into the vicinity, new drones were found at the congregation areas on the first day in equal proportion with local drones. This was true for congregation zones both near and distant to the apiary (2-3 km)...

"Drone congregation areas are commonly visited by drones from almost every apiary in the neighborhood..

"Areas as far as five km from an apiary may be visited regularly by numerous drones; some drones were found coming from more than six km away...

"Although the number of drones in a congregation area is quite variable, one such area had an estimated 25,000 drones from more than 200 colonies (Winston 1987). Several regularly frequented DCA’s were observed 500-1000 m from the nearest apiary.

"it was determined that the composition of the DCA contained equal representation from the local colonies, approximately 240 in number. Considering the density of colonies around the congregation area and average flight ranges of males, the results suggested that most colonies within the recruitment parameter of a DCA delegated equal proportions of males to a DCA. Consequently, the relatedness of a queen to her mates – and ultimately the inbreeding coefficient of the progeny – should be minimal. The relatedness among the drones mated to a common queen is also very low, maximizing the genetic diversity among the different patrilines (paternal sub-families) of a colony."

Now, reading that, I feel like it really wouldn't make a bit of difference if I went to the trouble of locating drone yards a mile away. All the DCA's in the area are still going to be frequented by those drones; in relatively equal parts to other colonies in the area. So diversity is maintained through the drones splitting up and spreading themselves out between DCA's. Queens don't really need to do anything to "avoid" their own drones, as the genetics are as diverse as there are enough healthy colonies in the area to produce drones.

It seems to me that it is enough for me to maintain healthy bees, graft queens and open mate. My colonies will influence the gene pool of the area proportionately.

So if you really want to influence the genetics, you have to have more colonies in the area than anyone else. And that "flooding the area" approach is done by many, and has been done for a long time.

Trying to maintain yards at distances for better mating with your own queens might just be a waste of time...

Re: Treatment Free: It's a path, not a solution

Erickson published the "recipe" for breeding resistant stock in 2000. This recipe is very distinct from an undirected "Bond" approach.
His six steps are:
1. Identify Varroa-tolerant colonies in your
apiaries.
2. Move all colonies identified as Varroa tolerant
to a single isolated test apiary. This
apiary should be at least 3-4 miles from
managed colonies treated for mite control.
3. Monitor Varroa levels in the selected
colonies every three months.
4. Graft only from those colonies with the
lowest mite loads…Never use colonies
with known problems such as disease,
poor productivity or unacceptable defensive
behavior, no matter how Varroa-tolerant
they may appear.
5.Mate all queens in the isolation test apiary.
6. Requeen colonies in your other apiaries
as queens become available. Once requeened,
these colonies become candidates
for future selections of improved
Varroa-tolerance, hence, the need for
good record keeping. (viz: http://xa.yimg.com/kq/groups/1694632...bee+RECIPE.pdf )

The promoters of a "Live-and-let-die" theory don't address the issue of inbreeding or genetic swamping -- the Erickson prescription and the Russian program address these explicitly.

Note they did 3 conditions: Resistant x Resistant crosses, R x Control , and C x C. The R x R queens were 100% hygenic, but produced on 1/2 the brood of free mated sisters. The loss of productivity is the mark of inbreeding. The Russian breeding program now takes out-crossing very seriously through grafting from one lineage for the virgin queens and yearly drone hive circulation from out-yards to saturate drones of a different lineage.

Improved selection requires A) isolation and B) saturation. There is very strong inertia in the bee breeding system (promiscuous obligate out-crossing) to revert to the normal genotype.

Re: Treatment Free: It's a path, not a solution

Originally Posted by Adam Foster Collins

Trying to maintain yards at distances for better mating with your own queens might just be a waste of time... Adam

It might be unnecessary, but it might also tip the scales your way. It will be dependent on how many treaters you have around, and how many resistant hives you have. You wouldn't expect to be able to maintain resistance with a few hundred treated hives around if you only had half a dozen. From that extreme example, and its reverse, you can extrapolate that the more you can get your drones into the game, the better.

As I said before, it seems to me that more attention you pay to this aspect, the more you increase your chances of success - at least if there are treaters around. If there are ferals all around your yard its a different story. I haven't read anything yet that makes me think its not a good idea, for me, to try to maintain say 4 outstands at a mile or two's distance around my yard as a genetic measure. And to encourage them to raise good numbers of drones.

We've read that ""it was determined that the composition of the DCA contained equal representation from the local colonies... " and that DCA's are populated more by nearer colonies. The latter makes more sense to me. As distance increases the likelihood of drones from a given colony must decrease.

I've read somewhere that you only need a few patrilines with mite-management behaviours to provide resistance. Probably there's an optimum of some sort, though given that there are several distinct behaviours the picture must be rather complex. But I think an equally important issue is that you want to maximise the chances of the daughter queens of the one mated to carry the right genes - not just for immediate purposes, but into the future. The next generation queen will be a product at random of her mother and one of the mated drones, and may or may not inherit the required behaviours from her mother (50% chance in each case). So the more resistance-carrying drones her mother has mated with the better - at least up to a point.

That's my attempt at rationalising matters on the info we've seen. But really I'm running with the intuition that more good colonies * more drones = more positive matings, and the longstanding understanding of people like Ruttner, Manley, and Solomon, that keeping dedicated drone colonies around a mating yard makes a positive difference. It makes sense, whereas taking no action against my local treaters doesn't. I don't need to know the ins and outs of it all.